(navigation image)
Home American Libraries | Canadian Libraries | Universal Library | Community Texts | Project Gutenberg | Children's Library | Biodiversity Heritage Library | Additional Collections
Search: Advanced Search
Anonymous User (login or join us)
Upload
See other formats

Full text of "Text Book Of Mechanical Engineering"

Examples.
DATA FOR COTTON ROPES, WHEN V = 4700 FT. PER M.

(Messrs. MUSGRAVE.)

537

Dia. of rope.
	Area of circle.
	Weight per foot.
	3*1 t
 ^,5 *
	Centrifugal stress
 I2WV*
	Effective tension
 (Tn-/n)
	H.P. transmitted.
	Centres pulley grooves.
	Dia. of smallest pulley.

ins.
	sq. ins. 1963
	Ibs. -08 1
	Ibs. 47
	Ibs. 16
	Ibs. 31
	4'43
	ins.
 I-
	ins.
 T5

I
	3067
	-125
	72
	24
	48
	6-84
	I
	18

i
	4417
	-184
	106
	35
	7*
	10*07
	l
	22

i
	*6ol3
	*25
	144
	48
	96
	13-67
	TI15-
	26

*      -7854
		'33
	190
	63
	127
	18-05
	4
	3

1 |   i    I ' 2 2 7 2
		51
	294
	98
	196
	27-9
	!TT
	37

i !  1-7671
		"74
	426
	142
	284
	-10-48
	4
	45

if     2-4053
		1 'OO
	576
	192
	384
	54'7
	4
	52

2   i 3*1416
		i'3
	75
	250
	500
	7 no
	2i
	60

The centrifugal stress is weight per foot x z/2 -r -, and the
fourth and sixth columns assume that /n = '2 Tn which gives Tn :
Vn : : 5 : i.    From the tension formula,

Log. 5 or 69897 - '4343  x (/* x 2*613)  x JSJ112L?

27-463

--18

i|7/ is the usual diameter for main rope.

Fig. 545 shews a spinning-mill driven by cotton ropes, the
power being-given to five floors by separate sets of ropes, a good
arrangement in case of breakdown. The slack side being upper-
most gives a large arc of contact. Fig. 546 shews a travelling
crane. The rope is endless, passing round the pullies D, H, A, G,
F, and E in succession, and kept taut by the weight at H. Worm
gear is used in taking off the power, at E for travelling, at B for
lifting and lowering, and at c for cross-traversing; and either rope
is put in gear by the press pullies a, fr, actuated by hand levers P, Q
E is reversed by friction gear worked from handle L.